1. Field of the Invention
The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus useful for employment in a copier, printer, or facsimile incorporating an automatic document feeder that performs automatic feeding of source documents, and a multifunctional composite apparatus that integrates these machines.
2. Description of the Related Art
In line with the digitalization of text data and image data in recent years, by far the most frequent kind of printout by multifunctional image forming apparatuses of this kind used in general offices and so forth is that of electronic data transmitted from a PC, FAX, or similar device.
While the trend is for the frequency of such electronic data printout to continue to increase among multifunctional image forming apparatuses of this kind, the copying of paper documents, book source documents, and the like is also necessary from time to time, and therefore a reading section for reading these source documents is also provided in these apparatuses.
With a conventional image forming apparatus of this kind, a source document holding platform and operation panel are generally positioned on the top of the main body of the apparatus to improve operability, and a sheet ejection tray of a sheet ejection section that holds a printed sheet that has undergone image formation is positioned so as to project at the side of the main body of the apparatus. Consequently, with this kind of image forming apparatus, an area for the projection of the sheet ejection tray is necessary at the side of the main body of the apparatus, and the required footprint (installation area) is larger than it appears.
For this reason, in recent years an image forming apparatus has been proposed that has a configuration whereby a space is formed in the waist section of the main body of the apparatus between the reading section positioned on the top of the main body of the apparatus and an image forming section positioned below this reading section, and an ejection section is formed in this space in the waist section of the main body of the apparatus (see, for example, Unexamined Japanese Patent Publication No. 2003-307996 (hereinafter referred to as patent document 1)).
An advantage of this image forming apparatus is that, since a printed sheet on which an image has been formed, fed from a feeding section below the image forming section, is ejected into an ejection section positioned in a space in the waist section of the main body of the apparatus, the footprint can be kept small.
However, while the footprint of an image forming apparatus with this kind of configuration can be kept small, there is an essential irrationality in the configuration in that it is awkward to check and remove a printed sheet that has undergone image formation because there is an operation panel operated by the user and a reading section above the ejection section.
That is to say, the image forming apparatus described in patent document 1 has a configuration such that a printed sheet that has undergone image formation, ejected into and held in the ejection section positioned in the waist section of the main body of the apparatus, is hidden behind the reading section, the operation panel on the front of the main body of the apparatus, or the like.
Consequently, with this image forming apparatus, it is difficult to check the state of a printed sheet that has undergone image formation by means of electronic data from a PC or the like for which image forming frequency is higher than for copying of paper documents, book source documents, or the like. Also, the configuration makes it difficult to remove an ejected printed sheet from the ejection section. Furthermore, with this image forming apparatus, since the ejection section is formed in a space in the waist section of the main body of the apparatus, the housing structure and exterior configuration are complicated. Moreover, with this image forming apparatus, it is necessary to form a large ejection section space in order to facilitate handling of printed sheets on which electronic data has been printed out from a PC or the like with a high image forming frequency as described above. Consequently, extra costs are necessary in order to maintain the strength of the main body of the apparatus, and so forth.
It is thus desirable for an image forming apparatus of this kind to have a configuration that allows the footprint of the main body of the apparatus to be kept small while also facilitating checking and removal of a printed sheet that has undergone image formation. An image forming apparatus in which the ejection section for a printed sheet that has undergone image formation is positioned above the source document placement section of the reading section is known as an image forming apparatus that meets this requirement (see, for example, Unexamined Japanese Patent Publication No. 2001-215759 (hereinafter referred to as patent document 2)).
In the image forming apparatus described in this patent document 2, a printed sheet that has undergone image formation is ejected onto the uppermost part of the main body of the apparatus, enabling the footprint of the main body of the apparatus to be made small while allowing checking and removal of a printed sheet that has undergone image formation to be performed easily.
However, in the case of the image forming apparatus described in patent document 2, a printed sheet that has undergone image formation is ejected onto a source document holding platform (contact glass) on which a source document to be copied is placed manually by the user. Therefore, this image forming apparatus has a configuration such that, when an automatic document feeder that feeds source documents automatically is positioned above this source document holding platform, a printed sheet that has undergone image formation is ejected below the source document feed tray and source document ejection tray of the automatic document feeder.
Consequently, with this image forming apparatus, when an automatic document feeder is provided a printed sheet that has undergone image formation is hidden beneath the source document feed tray and source document ejection tray, as in the case of the image forming apparatus of patent document 1. The configuration is thus inconvenient from the standpoint of checking and removing printed sheets.
Thus, in the image forming apparatus described in patent document 2, the source document feed tray and source document ejection tray are positioned slantwise, facilitating checking and removal of an ejected printed sheet. However, with an image forming apparatus having this kind of a configuration, the main body of the apparatus tends to be large, and the opening/closing trajectories of the source document feed tray and source document ejection tray of the automatic document feeder are wide, increasing the space occupied around the main body of the apparatus.
Therefore, in the case of an image forming apparatus equipped with an automatic document feeder, it is desirable for a printed sheet to be ejected above the source document feed tray. However, if this is done, a printed sheet will be ejected on top of a feed source document placed on the source document feed tray, resulting in the problem of an ejected printed sheet being automatically fed by the source document feeding section of the automatic document feeder.